1. Field of the Invention
This invention relates to a material application means and more particularly to a material application means adapted to apply stabilizer ply material having cords disposed at an angle therein to a tire building drum. Specifically, the instant invention relates to a transfer and application means used in conjunction with a cutter means to cut a pre-determined length of stabilizer ply material from a continuous roll of stabilizer ply material and apply said length to a tire building drum. The instant invention employs means for cutting the stabilizer ply material between the adjacent cords embedded therein and further has means for measuring of the angle of the cut so produced. The angled ends of the length of stabilizer ply material are adjusted during application to the tire building drum in order to cause the ends of said lengths to assume the same angle. A pair of wheels having pointed projections thereon are used to center the stabilizer ply material within the application means.
2. Description of the Prior Art
Means for material application are old in the art as evidenced by: U.S. Pat. No. 1,938,787 to Abbott which discloses a transfer drum having vacuum air circuits for ply attachment and means to cut the material along a helix. There is also disclosed a slight stretching of the ply material during the application process. U.S. Pat. No. 2,918,105 to Harris discloses a transfer drum having holes in the surface thereof through which suction may be applied to hold a severed band and transfer the same to a tire building drum. U.S. Pat. No. 3,071,179 to Tourtellotte et al discloses a tire apparatus utilizing a belt transfer mechanism. U.S. Pat. No. 3,100,731 to Brey discloses a mechanism for joining a leading edge of fabric cut on a bias to the trailing end. U.S. Pat. No. 3,157,542 to Trevaskis discloses a transfer drum and a cutter operative to cut a given length of ply. The edge of the severed length is pulled into alignment by means of the knife. U.S. Pat. No. 3,192,094 to Phillips et al discloses a means to sever ply material and a means to adjust the bias angle of the ply material. U.S. Pat. No. 3,591,439 to Leblond et al discloses a transfer drum and a cutter for the fabric on the drum. A centering device is provided for assuring alignment of the strip with respect to the drum. U.S. Pat. No. 3,595,724 to Leblond discloses the use of an applicator arm. U.S. Pat. No. 3,607,555 to Leblond, et al discloses a transfer drum and a breaker strip centering device. U.S. Pat. No. 3,654,828 to Leblond, et al discloses a transfer drum and aligning means, a cutter which cuts the ply on a helix and locating blocks which determine the length of the severed strip. U.S. Pat. No. 3,623,932 to Woodhall discloses the use of heated cutting knives. U.S. Pat. No. 3,732,767 to Habert discloses adjustable cutters, a drum, and a cutter movable along a helix. U.S. Pat. No. 3,803,965 to Alderfer discloses a vacuum pickup to pick up a severed strip and place it in a properly oriented position. U.S. Pat. No. 3,844,871 to Habert et al. discloses a breaker strip applicator means. U.S. Pat. No. 3,852,142 to Leblond et al discloses a transfer drum cutting means and a centering means. U.S. Pat. No. 3,899,383 to Schultz discloses a drum 4 applying a strip. U.S. Pat. No. 3,904,471 to Kubinski discloses a transfer drum and a means to cut the strip. U.S. Pat. No. 4,053,342 to Appleby discloses a vacuum manifold as well as the use of air pressure to release a tire band from the surface of the drum. U.S. Pat. No. 4,163,685 to Kubinski discloses a segmented drum. U.S. Pat. No. 4,170,509 to Kubinski discloses a drum made of segments and a single knife blade. Canadian Pat. No. 628,998 discloses the use of a vacuum clamp to hold the fabric and a photo cell control therefor. In addition, there is disclosed air employed as a flotation means to support the ply while it is moved and an aligning means to ensure that the ends of the fabric are properly aligned for joining. U.S. Pat. No. 3,130,100 to Hasselquist discloses an angular adjustment device that is utilized in order that fabric pieces bias cut at different bias angles can be butt splices. U.S. Pat. No. 3,676,259 to Appleby, et al., discloses a means for sensing the edge location of the ply and a device to move the supporting truck and surface drive as a unit to correct deviation from the desired edge location of the ply. U.S. Pat. No. 3,731,571 to Larson, discloses a pivoting guide to correct the irregularity of the strip being fed to a cutter.
The typical prior art procedure for cutting tire stabilizer plies having biased reinforcing cords therein and transferring same to a drum involves an operator utilizing a manual tire assembly machine. The operator typically pulls the leading edge of the stabilizer ply material from a server and affixes the leading end to a tire building drum. The tire building drum is then caused to be rotated by the operator. The tire stabilizer ply material is then wrapped about the tire building drum. The tire building drum is caused to make approximately one complete revolution after which its rotation is stopped. The operator then manually determines where the stabilizer ply material should be cut and then manually makes the cut of the stabilizer ply material along the axis of the cord members embedded therein in such a fashion as to cut the material between the cord members. The operator then manually manipulates the trailing edge of the stabilizer ply material in order to cause it to abut the leading edge of the stabilizer ply material. Often this requires considerable adjustment on the part of the operator since the angle of the cords at the leading edge of the stabilizer ply material may vary substantially from the angle of the cords in the trailing edge of the stabilizer ply material. After the operator has sufficiently adjusted by twisting and stretching the trailing edge of the stabilizer ply material, the two edges are abutted and stitched in order to form the stabilizer ply.
Many of the attempts to automate the stabilizer ply application process have focused on the cutting procedure. For example, U.S. Pat. No. 2,665,757 discloses a means to assure cutting between the cords by providing two knives with sharp points to penetrate the fabric and blunt edges to effect a tearing of the fabric between the cords by movement of the knives in opposite directions. However, the concept provided nothing to assure that the original vertical plunge of the sharp knives did not damage a cord. Furthermore, the action does not provide a clean-cut edge. In U.S. Pat. No. 3,641,855, a concept is disclosed whereby two knives sever the material near the center and move in opposite directions theoretically between the cords. The knives are hinged to provide somewhat of a novel motion in an attempt to avoid the cords. However, since one edge of each knife is fixed at the hinge, the preferred movement of parallelism to a cord is lost and contact with a cord, baring same, is highly likely. Finally, U.S. Pat. No. 3,789,712 discloses vibrating a knife blade in an attempt to avoid cords.
Another problem addressed by some attempts at automation relates to the adjustment of the knife angle for processing tire ply stock having differently biased reinforcing cords. U.S. Pat. No. 3,192,094, although relating to the construction of the roll of ply stock used for a tire server, attempts to solve the problem by altering the angle at which the material is fed to the cutting area. Such a complex procedure would not lend itself well to the system of cutting the ply stock supplied by a server and transfering same to a drum. U.S. Pat. No. 3,641,555 merely adjusts the angle at which a cut may be made but does not take into account the fact that all cords in the fabric, although at a nominal specified angle, are not always at the same angle. Therefore, if cuts are made between cords at various longitudinal locations along the fabric, the two cuts will not always be at the same angle.
In most attempts at automation, no satisfactory means has been developed to hold the fabric in place during cutting. Such is critical to a perfect cut, particularly when one is attempting to make a precise cut between reinforcing cords. Most attempts in this regard have used back-to-back knives moving in opposite directions to minimize materials shifting. Such is shown in U.S. Pat. No. 2,665,757; 3,641,855 and 3,762,259. However, even these disclosures recognize the imperfections in this concept in that the disclosure of U.S. Pat. No. 3,762,259 utilizes a mechanical clamp to assure that the fabric does not shift during cutting.
There is, therefore, a need for an apparatus which may be utilized to automatically sever a portion of stabilizer ply material having cords biased at an angle therein from a continuous roll of such material and apply same to a tire building drum wherein the leading edge of the stabilizer ply material and the trailing edge of the stabilizer ply material may be automatically aligned in order to produce an improved butt splice of the respective edges. Further, there is a need for a means adapted to sever a stabilizer ply material having cords biased at an angle therein in such a fashion as to cut the stabilizer ply between the cords in order not to bare any of the cords. The instant invention provides such means allowing for the precise application of stabilizer ply material to a tire building drum.